diff options
Diffstat (limited to 'target/arm/arm-powerctl.c')
| -rw-r--r-- | target/arm/arm-powerctl.c | 368 |
1 files changed, 368 insertions, 0 deletions
diff --git a/target/arm/arm-powerctl.c b/target/arm/arm-powerctl.c new file mode 100644 index 000000000..b75f813b4 --- /dev/null +++ b/target/arm/arm-powerctl.c @@ -0,0 +1,368 @@ +/* + * QEMU support -- ARM Power Control specific functions. + * + * Copyright (c) 2016 Jean-Christophe Dubois + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + * + */ + +#include "qemu/osdep.h" +#include "cpu.h" +#include "cpu-qom.h" +#include "internals.h" +#include "arm-powerctl.h" +#include "qemu/log.h" +#include "qemu/main-loop.h" + +#ifndef DEBUG_ARM_POWERCTL +#define DEBUG_ARM_POWERCTL 0 +#endif + +#define DPRINTF(fmt, args...) \ + do { \ + if (DEBUG_ARM_POWERCTL) { \ + fprintf(stderr, "[ARM]%s: " fmt , __func__, ##args); \ + } \ + } while (0) + +CPUState *arm_get_cpu_by_id(uint64_t id) +{ + CPUState *cpu; + + DPRINTF("cpu %" PRId64 "\n", id); + + CPU_FOREACH(cpu) { + ARMCPU *armcpu = ARM_CPU(cpu); + + if (armcpu->mp_affinity == id) { + return cpu; + } + } + + qemu_log_mask(LOG_GUEST_ERROR, + "[ARM]%s: Requesting unknown CPU %" PRId64 "\n", + __func__, id); + + return NULL; +} + +struct CpuOnInfo { + uint64_t entry; + uint64_t context_id; + uint32_t target_el; + bool target_aa64; +}; + + +static void arm_set_cpu_on_async_work(CPUState *target_cpu_state, + run_on_cpu_data data) +{ + ARMCPU *target_cpu = ARM_CPU(target_cpu_state); + struct CpuOnInfo *info = (struct CpuOnInfo *) data.host_ptr; + + /* Initialize the cpu we are turning on */ + cpu_reset(target_cpu_state); + target_cpu_state->halted = 0; + + if (info->target_aa64) { + if ((info->target_el < 3) && arm_feature(&target_cpu->env, + ARM_FEATURE_EL3)) { + /* + * As target mode is AArch64, we need to set lower + * exception level (the requested level 2) to AArch64 + */ + target_cpu->env.cp15.scr_el3 |= SCR_RW; + } + + if ((info->target_el < 2) && arm_feature(&target_cpu->env, + ARM_FEATURE_EL2)) { + /* + * As target mode is AArch64, we need to set lower + * exception level (the requested level 1) to AArch64 + */ + target_cpu->env.cp15.hcr_el2 |= HCR_RW; + } + + target_cpu->env.pstate = aarch64_pstate_mode(info->target_el, true); + } else { + /* We are requested to boot in AArch32 mode */ + static const uint32_t mode_for_el[] = { 0, + ARM_CPU_MODE_SVC, + ARM_CPU_MODE_HYP, + ARM_CPU_MODE_SVC }; + + cpsr_write(&target_cpu->env, mode_for_el[info->target_el], CPSR_M, + CPSRWriteRaw); + } + + if (info->target_el == 3) { + /* Processor is in secure mode */ + target_cpu->env.cp15.scr_el3 &= ~SCR_NS; + } else { + /* Processor is not in secure mode */ + target_cpu->env.cp15.scr_el3 |= SCR_NS; + + /* Set NSACR.{CP11,CP10} so NS can access the FPU */ + target_cpu->env.cp15.nsacr |= 3 << 10; + + /* + * If QEMU is providing the equivalent of EL3 firmware, then we need + * to make sure a CPU targeting EL2 comes out of reset with a + * functional HVC insn. + */ + if (arm_feature(&target_cpu->env, ARM_FEATURE_EL3) + && info->target_el == 2) { + target_cpu->env.cp15.scr_el3 |= SCR_HCE; + } + } + + /* We check if the started CPU is now at the correct level */ + assert(info->target_el == arm_current_el(&target_cpu->env)); + + if (info->target_aa64) { + target_cpu->env.xregs[0] = info->context_id; + } else { + target_cpu->env.regs[0] = info->context_id; + } + + /* CP15 update requires rebuilding hflags */ + arm_rebuild_hflags(&target_cpu->env); + + /* Start the new CPU at the requested address */ + cpu_set_pc(target_cpu_state, info->entry); + + g_free(info); + + /* Finally set the power status */ + assert(qemu_mutex_iothread_locked()); + target_cpu->power_state = PSCI_ON; +} + +int arm_set_cpu_on(uint64_t cpuid, uint64_t entry, uint64_t context_id, + uint32_t target_el, bool target_aa64) +{ + CPUState *target_cpu_state; + ARMCPU *target_cpu; + struct CpuOnInfo *info; + + assert(qemu_mutex_iothread_locked()); + + DPRINTF("cpu %" PRId64 " (EL %d, %s) @ 0x%" PRIx64 " with R0 = 0x%" PRIx64 + "\n", cpuid, target_el, target_aa64 ? "aarch64" : "aarch32", entry, + context_id); + + /* requested EL level need to be in the 1 to 3 range */ + assert((target_el > 0) && (target_el < 4)); + + if (target_aa64 && (entry & 3)) { + /* + * if we are booting in AArch64 mode then "entry" needs to be 4 bytes + * aligned. + */ + return QEMU_ARM_POWERCTL_INVALID_PARAM; + } + + /* Retrieve the cpu we are powering up */ + target_cpu_state = arm_get_cpu_by_id(cpuid); + if (!target_cpu_state) { + /* The cpu was not found */ + return QEMU_ARM_POWERCTL_INVALID_PARAM; + } + + target_cpu = ARM_CPU(target_cpu_state); + if (target_cpu->power_state == PSCI_ON) { + qemu_log_mask(LOG_GUEST_ERROR, + "[ARM]%s: CPU %" PRId64 " is already on\n", + __func__, cpuid); + return QEMU_ARM_POWERCTL_ALREADY_ON; + } + + /* + * The newly brought CPU is requested to enter the exception level + * "target_el" and be in the requested mode (AArch64 or AArch32). + */ + + if (((target_el == 3) && !arm_feature(&target_cpu->env, ARM_FEATURE_EL3)) || + ((target_el == 2) && !arm_feature(&target_cpu->env, ARM_FEATURE_EL2))) { + /* + * The CPU does not support requested level + */ + return QEMU_ARM_POWERCTL_INVALID_PARAM; + } + + if (!target_aa64 && arm_feature(&target_cpu->env, ARM_FEATURE_AARCH64)) { + /* + * For now we don't support booting an AArch64 CPU in AArch32 mode + * TODO: We should add this support later + */ + qemu_log_mask(LOG_UNIMP, + "[ARM]%s: Starting AArch64 CPU %" PRId64 + " in AArch32 mode is not supported yet\n", + __func__, cpuid); + return QEMU_ARM_POWERCTL_INVALID_PARAM; + } + + /* + * If another CPU has powered the target on we are in the state + * ON_PENDING and additional attempts to power on the CPU should + * fail (see 6.6 Implementation CPU_ON/CPU_OFF races in the PSCI + * spec) + */ + if (target_cpu->power_state == PSCI_ON_PENDING) { + qemu_log_mask(LOG_GUEST_ERROR, + "[ARM]%s: CPU %" PRId64 " is already powering on\n", + __func__, cpuid); + return QEMU_ARM_POWERCTL_ON_PENDING; + } + + /* To avoid racing with a CPU we are just kicking off we do the + * final bit of preparation for the work in the target CPUs + * context. + */ + info = g_new(struct CpuOnInfo, 1); + info->entry = entry; + info->context_id = context_id; + info->target_el = target_el; + info->target_aa64 = target_aa64; + + async_run_on_cpu(target_cpu_state, arm_set_cpu_on_async_work, + RUN_ON_CPU_HOST_PTR(info)); + + /* We are good to go */ + return QEMU_ARM_POWERCTL_RET_SUCCESS; +} + +static void arm_set_cpu_on_and_reset_async_work(CPUState *target_cpu_state, + run_on_cpu_data data) +{ + ARMCPU *target_cpu = ARM_CPU(target_cpu_state); + + /* Initialize the cpu we are turning on */ + cpu_reset(target_cpu_state); + target_cpu_state->halted = 0; + + /* Finally set the power status */ + assert(qemu_mutex_iothread_locked()); + target_cpu->power_state = PSCI_ON; +} + +int arm_set_cpu_on_and_reset(uint64_t cpuid) +{ + CPUState *target_cpu_state; + ARMCPU *target_cpu; + + assert(qemu_mutex_iothread_locked()); + + /* Retrieve the cpu we are powering up */ + target_cpu_state = arm_get_cpu_by_id(cpuid); + if (!target_cpu_state) { + /* The cpu was not found */ + return QEMU_ARM_POWERCTL_INVALID_PARAM; + } + + target_cpu = ARM_CPU(target_cpu_state); + if (target_cpu->power_state == PSCI_ON) { + qemu_log_mask(LOG_GUEST_ERROR, + "[ARM]%s: CPU %" PRId64 " is already on\n", + __func__, cpuid); + return QEMU_ARM_POWERCTL_ALREADY_ON; + } + + /* + * If another CPU has powered the target on we are in the state + * ON_PENDING and additional attempts to power on the CPU should + * fail (see 6.6 Implementation CPU_ON/CPU_OFF races in the PSCI + * spec) + */ + if (target_cpu->power_state == PSCI_ON_PENDING) { + qemu_log_mask(LOG_GUEST_ERROR, + "[ARM]%s: CPU %" PRId64 " is already powering on\n", + __func__, cpuid); + return QEMU_ARM_POWERCTL_ON_PENDING; + } + + async_run_on_cpu(target_cpu_state, arm_set_cpu_on_and_reset_async_work, + RUN_ON_CPU_NULL); + + /* We are good to go */ + return QEMU_ARM_POWERCTL_RET_SUCCESS; +} + +static void arm_set_cpu_off_async_work(CPUState *target_cpu_state, + run_on_cpu_data data) +{ + ARMCPU *target_cpu = ARM_CPU(target_cpu_state); + + assert(qemu_mutex_iothread_locked()); + target_cpu->power_state = PSCI_OFF; + target_cpu_state->halted = 1; + target_cpu_state->exception_index = EXCP_HLT; +} + +int arm_set_cpu_off(uint64_t cpuid) +{ + CPUState *target_cpu_state; + ARMCPU *target_cpu; + + assert(qemu_mutex_iothread_locked()); + + DPRINTF("cpu %" PRId64 "\n", cpuid); + + /* change to the cpu we are powering up */ + target_cpu_state = arm_get_cpu_by_id(cpuid); + if (!target_cpu_state) { + return QEMU_ARM_POWERCTL_INVALID_PARAM; + } + target_cpu = ARM_CPU(target_cpu_state); + if (target_cpu->power_state == PSCI_OFF) { + qemu_log_mask(LOG_GUEST_ERROR, + "[ARM]%s: CPU %" PRId64 " is already off\n", + __func__, cpuid); + return QEMU_ARM_POWERCTL_IS_OFF; + } + + /* Queue work to run under the target vCPUs context */ + async_run_on_cpu(target_cpu_state, arm_set_cpu_off_async_work, + RUN_ON_CPU_NULL); + + return QEMU_ARM_POWERCTL_RET_SUCCESS; +} + +static void arm_reset_cpu_async_work(CPUState *target_cpu_state, + run_on_cpu_data data) +{ + /* Reset the cpu */ + cpu_reset(target_cpu_state); +} + +int arm_reset_cpu(uint64_t cpuid) +{ + CPUState *target_cpu_state; + ARMCPU *target_cpu; + + assert(qemu_mutex_iothread_locked()); + + DPRINTF("cpu %" PRId64 "\n", cpuid); + + /* change to the cpu we are resetting */ + target_cpu_state = arm_get_cpu_by_id(cpuid); + if (!target_cpu_state) { + return QEMU_ARM_POWERCTL_INVALID_PARAM; + } + target_cpu = ARM_CPU(target_cpu_state); + + if (target_cpu->power_state == PSCI_OFF) { + qemu_log_mask(LOG_GUEST_ERROR, + "[ARM]%s: CPU %" PRId64 " is off\n", + __func__, cpuid); + return QEMU_ARM_POWERCTL_IS_OFF; + } + + /* Queue work to run under the target vCPUs context */ + async_run_on_cpu(target_cpu_state, arm_reset_cpu_async_work, + RUN_ON_CPU_NULL); + + return QEMU_ARM_POWERCTL_RET_SUCCESS; +} |